21397504798 has 8 divisors (see below), whose sum is σ = 32188224600. Its totient is φ = 10668096600.

The previous prime is 21397504769. The next prime is 21397504837. The reversal of 21397504798 is 89740579312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 15327028 + ... + 15328423.

It is an arithmetic number, because the mean of its divisors is an integer number (4023528075).

Almost surely, 2^21397504798 is an apocalyptic number.

21397504798 is a deficient number, since it is larger than the sum of its proper divisors (10790719802).

21397504798 is a wasteful number, since it uses less digits than its factorization.

21397504798 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30655802.

The product of its (nonzero) digits is 3810240, while the sum is 55.

The spelling of 21397504798 in words is "twenty-one billion, three hundred ninety-seven million, five hundred four thousand, seven hundred ninety-eight".